Distribution: S - Cal (Puntillo 1996, Brackel 2016).
Description: Thallus not evident, not lichenized. Apothecia short-stalked, 0.12-0.2 mm high, pin-like, developing on the thalli of epiphytic Lecanora-species. Stalk black in upper part, pale brown to whitish in lower part, epruinose, 50-60 µm thick, formed by intertwined, brownish hyphae. Capitulum lenticular, black, epruinose, 0.1-0.2 mm across. Excipulum brown, of intertwined hyphae; epithecium poorly evident; mazaedium not present; hypothecium brown. Asci 8-spored, cylindrical to subclavate, with a thickened apex penetrated by a narrow canal, formed singly, persisting until the uniseriately arranged spores are mature. Ascospores 1-celled, greyish brown to dark brown at maturity, narrowly ellipsoid, (4.5-)5.3-7(-7.5) x 2.5-3(-3.5) µm, with a minutely verrucose surface. Photobiont absent. Spot tests: ascocarps K-, C-, KC-, P-. Chemistry: without lichen substances.
Note: Tibell & Ryman (1995) did not recognize Ch. treicheliana as a distinct species and presumed it might be a synonym of Ch. hospitans. However, according to Gasparyan & al. (2014), Ch. hospitans shows a faint K+ reaction of the ascomata, and its stalk and ascospores are distinctly larger (7.8-9.6 × 3.9-5 µm). The species, which is also known from Austria, Poland and Armenia, occurs as a parasite on the thalli of epiphytic Lecanora-species.